Methods and apparatus for maintaining low non-uniformity over target life

ABSTRACT

Embodiments of improved apparatus for maintaining low non-uniformity over the life of a target are provided herein. In some embodiments, an apparatus includes a substrate support within a volume of a chamber body, opposite a target assembly of a lid atop the chamber body, with a surface; a shield disposed within the chamber body comprising one or more sidewalls surrounding the volume, the shield extending downward to below a top surface of the substrate support, radially inward, and returning upward forming an extending lip; and a first ring having (i) a first portion comprising an opening having a ceramic isolator, disposed therein, resting on top of the extending lip, and (ii) a second portion extending away from the first portion toward the surface, wherein the substrate support, over a life of the target, is configured to raise and lower, relative to the first ring, a substrate disposed on the surface.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a continuation of co-pending U.S. patent applicationSer. No. 14/522,066, filed Oct. 23, 2014, which claims benefit of U.S.provisional patent application Ser. No. 62/040,837, filed Aug. 22, 2014.Each of the aforementioned patent applications is herein incorporated byreference in its entirety.

FIELD

Embodiments of the present disclosure generally relate to substrateprocessing systems.

BACKGROUND

Physical vapor deposition (PVD) processes can use radio frequency (RF)energy to enhance substrate processing for certain applications. Forexample, RF energy may be provided to a target of a PVD chamber tofacilitate sputtering of materials from the target and depositing thesputtered materials onto a substrate disposed in the PVD chamber. Theinventors have observed that process non-uniformity issues, such asnon-uniform film deposition, may arise in such PVD chambers undercertain operating conditions. The inventors believe that suchnon-uniform film deposition may occur due to a change in deposition rateacross a substrate over the course of the life of a target.

Accordingly, the inventors have provided improved methods and apparatusfor maintaining low non-uniformity over the course of the life of atarget.

SUMMARY

Embodiments of improved methods and apparatus for maintaining lownon-uniformity over the course of the life of a target are providedherein. In some embodiments, a method of processing a substrate in aphysical vapor deposition chamber includes: disposing a substrate atop asubstrate support having a cover ring that surrounds the substratesupport such that an upper surface of the substrate is positioned at afirst distance above an upper surface of the cover ring; sputtering asource material from a target disposed opposite the substrate support todeposit a film atop the substrate while maintaining the first distance;and lowering the substrate support with respect to the cover ring andsputtering the source material from the target to deposit films atopsubsequent substrates over a life of the target.

In some embodiments, a physical vapor deposition chamber includes: achamber body having a first volume; a chamber lid comprising a targetassembly disposed atop the chamber body; a substrate support disposedwithin the first volume, opposite the target assembly, and having asubstrate supporting surface; a shield disposed within the chamber bodycomprising one or more sidewalls configured to surround the firstvolume, wherein the shield extends downward to below a top surface ofthe substrate support, radially inward, and then returns upward to forman upwardly extending lip; a first ring having a first portion and asecond portion, wherein the first portion comprises an opening having aceramic isolator disposed therein, wherein the ceramic isolator rests onthe top of the upwardly extending lip of the shield, and wherein thesecond portion extends away from the first portion toward the substratesupporting surface, and wherein the substrate support, over a course ofa life of the target, is configured to raise and lower, relative to thefirst ring, a substrate disposed on the substrate supporting surface;and a second ring disposed about a peripheral edge of the substratesupport and adjacent to the substrate supporting surface.

In some embodiments, a method of processing a plurality of substrates ina physical vapor deposition chamber includes: (a) sputtering a sourcematerial from a target spaced opposite a substrate to deposit a filmatop the substrate, wherein the substrate is disposed atop a substratesupport having a cover ring that surrounds the substrate support suchthat an upper surface of the substrate is positioned at a first distancefrom an upper surface of the cover ring; (b) lowering the substratesupport; (c) sputtering the source material from the target to deposit afilm atop a subsequent substrate at a next position provided by thelowered substrate; and (d) repeating (b)-(c) until the source materialfrom the target is consumed.

Other and further embodiments of the present disclosure are describedbelow.

BRIEF DESCRIPTION OF THE DRAWINGS

Embodiments of the present disclosure, briefly summarized above anddiscussed in greater detail below, can be understood by reference to theillustrative embodiments of the disclosure depicted in the appendeddrawings. It is to be noted, however, that the appended drawingsillustrate only typical embodiments of this disclosure and are thereforenot to be considered limiting of its scope, for the disclosure may admitto other equally effective embodiments.

FIG. 1 depicts a schematic cross sectional view of a process chamberhaving a substrate support in accordance with some embodiments of thepresent disclosure.

FIG. 2 depicts a flow chart of a method for processing a substrate in aphysical vapor deposition chamber in accordance with some embodiments ofthe present disclosure.

FIG. 3A-3C depicts a partial schematic cross sectional view of asubstrate support and surrounding structure in accordance with someembodiments of the present disclosure.

To facilitate understanding, identical reference numerals have beenused, where possible, to designate identical elements that are common tothe figures. The figures are not drawn to scale and may be simplifiedfor clarity. It is contemplated that elements and features of oneembodiment may be beneficially incorporated in other embodiments withoutfurther recitation.

DETAILED DESCRIPTION

Improved methods and apparatus for maintaining low non-uniformity overthe course of the life of a target are provided herein. When depositinga film via a physical vapor deposition process, embodiments of theinventive process and apparatus described herein advantageously maintaina low film non-uniformity profile over the life of a target.

FIG. 1 depicts a simplified, cross-sectional view of a physical vapordeposition (PVD) chamber (chamber 100), suitable for performing themethod 200 described below. Examples of PVD chambers suitable formodification in accordance with the teachings provided herein includechambers having very high frequency (VHF) sources, the ALPS® Plus andSIP ENCORE® PVD processing chambers, both commercially available fromApplied Materials, Inc., of Santa Clara, Calif. Other processingchambers from Applied Materials, Inc. or other manufacturers may alsobenefit from modifications in accordance with the inventive apparatusdisclosed herein and be used to perform embodiments of the inventivemethods disclosed herein.

The chamber 100 contains a substrate support 102 for receiving asubstrate 104 on the substrate support, and a sputtering source, such asa target 106. In some embodiments, the substrate support is configuredas an electrostatic chuck The substrate support 102 may be locatedwithin a grounded enclosure wall (e.g., chamber wall 108), which may bea chamber wall (as shown) or a grounded shield (a ground shield 140 isshown covering at least some portions of the chamber 100 above thetarget 106. In some embodiments, the ground shield 140 could be extendedbelow the target to enclose the substrate support 102 as well).

In some embodiments, the process chamber includes a feed structure forcoupling RF and DC energy to the target 106. The feed structure is anapparatus for coupling RF and DC energy to the target, or to an assemblycontaining the target, for example, as described herein. A first end ofthe feed structure can be coupled to an RF power source 118 and a DCpower source 120, which can be respectively utilized to provide RF andDC energy to the target 106. For example, the DC power source 120 may beutilized to apply a negative voltage, or bias, to the target 106. Insome embodiments, RF energy supplied by the RF power source 118 mayrange in frequency from about 2 MHz to about 60 MHz, or, for example,non-limiting frequencies such as 2 MHz, 13.56 MHz, 27.12 MHz, 40.68 MHzor 60 MHz can be used. In some embodiments, a plurality of RF powersources may be provided (i.e., two or more) to provide RF energy in aplurality of the above frequencies. The feed structure may be fabricatedfrom suitable conductive materials to conduct the RF and DC energy fromthe RF power source 118 and the DC power source 120. In someembodiments, about 6 kW of 40 MHz RF is provided at the same time about1 kW of DC power is provided to produce the desired particle properties.In some embodiments, the RF power is provided at about 4 kW to about 8Kw at a frequency of about 13.56 MHz to about 60 MHz, and the DC powersimultaneously at about 0.5 kW to about 2 kW.

In some embodiments, the feed structure may have a suitable length thatfacilitates substantially uniform distribution of the respective RF andDC energy about the perimeter of the feed structure. For example, insome embodiments, the feed structure may have a length of between about1 to about 12 inches, or about 4 inches. In some embodiments, the bodymay have a length to inner diameter ratio of at least about 1:1.Providing a ratio of at least 1:1 or longer provides for more uniform RFdelivery from the feed structure (i.e., the RF energy is more uniformlydistributed about the feed structure to approximate RF coupling to thetrue center point of the feed structure). The inner diameter of the feedstructure may be as small as possible, for example, from about 1 inch toabout 6 inches, or about 4 inches in diameter. Providing a smaller innerdiameter facilitates improving the length to ID ratio without increasingthe length of the feed structure.

The second end of the feed structure may be coupled to a sourcedistribution plate 122. The source distribution plate includes a hole124 disposed through the source distribution plate 122 and aligned witha central opening of the feed structure. The source distribution plate122 may be fabricated from suitable conductive materials to conduct theRF and DC energy from the feed structure.

The source distribution plate 122 may be coupled to the target 106 via aconductive member 125. The conductive member 125 may be a tubular memberhaving a first end 126 coupled to a target-facing surface 128 of thesource distribution plate 122 proximate the peripheral edge of thesource distribution plate 122. The conductive member 125 furtherincludes a second end 130 coupled to a source distribution plate-facingsurface 132 of the target 106 (or to the backing plate 146 of the target106) proximate the peripheral edge of the target 106.

A cavity 134 may be defined by the inner-facing walls of the conductivemember 125, the target-facing surface 128 of the source distributionplate 122 and the source distribution plate-facing surface 132 of thetarget 106. The cavity 134 is fluidly coupled to the central opening ofthe body via the hole 124 of the source distribution plate 122. Thecavity 134 and the central opening of the body may be utilized to atleast partially house one or more portions of a rotatable magnetronassembly 136. In some embodiments, the cavity may be at least partiallyfilled with a cooling fluid, such as water (H₂O) or the like.

A ground shield 140 may be provided to cover the outside surfaces of thelid of the chamber 100. The ground shield 140 may be coupled to ground,for example, via the ground connection of the chamber body. The groundshield 140 has a central opening to allow the feed structure to passthrough the ground shield 140 to be coupled to the source distributionplate 122. The ground shield 140 may comprise any suitable conductivematerial, such as aluminum, copper, or the like. An insulative gap 139is provided between the ground shield 140 and the outer surfaces of thesource distribution plate 122, the conductive member 125, and the target106 (and/or backing plate 146) to prevent the RF and DC energy frombeing routed directly to ground. The insulative gap may be filled withair or some other suitable dielectric material, such as a ceramic, aplastic, or the like.

An isolator plate 138 may be disposed between the source distributionplate 122 and the ground shield 140 to prevent the RF and DC energy frombeing routed directly to ground. The isolator plate 138 has a centralopening to allow the feed structure to pass through the isolator plate138 and be coupled to the source distribution plate 122. The isolatorplate 138 may comprise a suitable dielectric material, such as aceramic, a plastic, or the like. Alternatively, an air gap may beprovided in place of the isolator plate 138. In embodiments where an airgap is provided in place of the isolator plate, the ground shield 140may be structurally sound enough to support any components resting uponthe ground shield 140.

The target 106 may be supported on a grounded conductive aluminumadapter 142 through a dielectric isolator 144. The target 106 comprisesa material to be deposited on the substrate 104 during sputtering, sucha metal or metal oxide. In some embodiments, the backing plate 146 maybe coupled to the source distribution plate-facing surface 132 of thetarget 106. The backing plate 146 may comprise a conductive material,such as copper-zinc, copper-chrome, or the same material as the target,such that RF and DC power can be coupled to the target 106 via thebacking plate 146. Alternatively, the backing plate 146 may benon-conductive and may include conductive elements (not shown) such aselectrical feedthroughs or the like for coupling the source distributionplate-facing surface 132 of the target 106 to the second end 130 of theconductive member 125. The backing plate 146 may be included forexample, to improve structural stability of the target 106.

The substrate support 102 has a material-receiving surface facing theprincipal surface of the target 106 and supports the substrate 104 to besputter coated in planar position opposite to the principal surface ofthe target 106. The substrate support 102 may support the substrate 104in a first volume 113 of the chamber 100. The first volume 113 isdefined as the region above the substrate support 102 during processing(for example, between the target 106 and the substrate support 102 whenin a processing position).

In some embodiments, the substrate support 102 may be vertically movablethrough a bellows 150 connected to a bottom chamber wall 152 to allowthe substrate 104 to be transferred onto the substrate support 102through a load lock valve (not shown) in the lower portion of processingthe chamber 100 and thereafter raised to a deposition, or processingposition. One or more processing gases may be supplied from a gas source154 through a mass flow controller 156 into the lower part of thechamber 100. An exhaust port 158 may be provided and coupled to a pump(not shown) via a valve 160 for exhausting the interior of the chamber100 and facilitating maintaining a pressure inside the chamber 100.

An RF bias power source 162 may be coupled to the substrate support 102in order to induce a negative DC bias on the substrate 104. In addition,in some embodiments, a negative DC self-bias may form on the substrate104 during processing. For example, RF power supplied by the RF biaspower source 162 may range in frequency from about 2 MHz to about 60MHz, for example, non-limiting frequencies such as 2 MHz, 13.56 MHz, or60 MHz can be used. Optionally, a second RF bias power source (notshown) may be coupled to the substrate support 102 and provide any ofthe frequencies discussed above for use with the RF bias power source162. In other applications, the substrate support 102 may be grounded orleft electrically floating. For example, a capacitance tuner 164 may becoupled to the substrate support for adjusting voltage on the substrate104 for applications where RF bias power may not be desired. In someembodiments, the capacitance tuner 164 may be used to adjust thesubstrate floating potential so that ion energy arriving at thesubstrate can be controlled. In some embodiments, the RF bias powersource 162 and the capacitance tuner 164 may both be appliedsimultaneously.

A rotatable magnetron assembly 136 may be positioned proximate a backsurface (e.g., source distribution plate-facing surface 132) of thetarget 106. The rotatable magnetron assembly 136 includes the magnetron107 which connects to a rotation shaft 170 coincident with the centralaxis of the chamber 100 and the substrate 104. A motor 172 can becoupled to the upper end of the rotation shaft 170 to drive rotation ofthe magnetron assembly 136. The magnets 103 produce a magnetic fieldwithin the chamber 100, generally parallel and close to the surface ofthe target 106 to trap electrons and increase the local plasma density,which in turn increases the sputtering rate. The magnets 103 produce anelectromagnetic field around the top of the chamber 100, and the magnetsare rotated to rotate the electromagnetic field which influences theplasma density of the process to more uniformly sputter the target 106.For example, the rotation shaft 170 may make about 0 to about 150rotations per minute.

The chamber 100 further includes a process kit shield, or shield 174, tosurround the processing, or first volume 113 of the chamber 100 and toprotect other chamber components from damage and/or contamination fromprocessing. In some embodiments, the shield 174 may be a grounded shieldconnected to a ledge 176 of an adapter 142

The shield 174 extends downward and may include one or more sidewalls180 configured to surround the first volume 113. The shield 174 extendsdownward along the walls of the adapter 142 and the chamber wall 108 tobelow an upper surface of the substrate support 102, radially inward,and then returns upward to form an upwardly extending lip 188, forexample, reaching an upper surface of the substrate support 102 (e.g.,forming a u-shaped portion 184 at the bottom). Alternatively, thebottommost portion of the shield 174 need not be a u-shaped portion 184and may have any suitable shape. A first ring 148 (i.e., a cover ring)rests on the top of the upwardly extending lip 188 of the shield 174when the substrate support 102 is in its lower, loading position (asshown in FIG. 3C). When the substrate support 102 is in its upperposition (as illustrated in FIG. 1 and FIG. 3A), the first ring 148rests on the top of the upwardly extending lip 188 of the shield 174 andthe outer periphery of the substrate support 102.

An additional second ring 111 (i.e., a deposition ring) may be used toprotect the substrate support 102 from sputter deposition. For example,the second ring 111 may be disposed about a peripheral edge of thesubstrate support 102 and adjacent to the substrate processing surface109 as illustrated in FIG. 1. In some embodiments, the second ring 111may shield exposed surfaces of the substrate support 102 as shown.

FIG. 2 depicts a method 200 of processing a substrate 104 in a physicalvapor deposition chamber, for example the chamber 100 depicted in FIG.1, in accordance with some embodiments of the present disclosure. Themethod 200 generally begins at 202, where a substrate 104 is disposedatop a substrate support 102. FIGS. 3A-3C depict schematic side views ofa portion of the substrate support 102 in accordance with someembodiments of the present disclosure.

As depicted in FIG. 3A, when the substrate support 102 is in the upperposition, the first ring 148 surrounds the substrate support 102 suchthat an upper surface of the substrate 104 is positioned at a firstdistance 300 above an upper surface of the first ring 148. In someembodiments, at the beginning of the target life, the first distance 300is any suitable distance to maintain a low non-uniformity of the filmdeposited on the substrate, for example above the upper surface of thefirst ring 148, or in some embodiments, about 3 mm above the uppersurface of the first ring 148. When at the first distance above theupper surface of the first ring 148, the first ring 148 does not shieldthe edges of the substrate 104 from deposition.

As depicted in FIG. 3A, the first ring 148 (i.e., a cover ring) has afirst portion 306 and a second portion 308 extending away from the firstportion 306 toward the substrate processing surface 109. The firstportion 306 comprises an opening 310 having a ceramic isolator 141disposed within the opening 310. When the substrate support 102 is inits upper position (as illustrated in FIG. 1 and FIG. 3A) the ceramicisolator 141 supports the first ring 148 on the top of the upwardlyextending lip 188 of the shield 174 and the second portion 308 of thefirst ring 148 rests on the second ring 111 at the outer periphery ofthe substrate support 102. The second portion 308 of the first ring 148comprises a peripheral edge 312 that is a horizontal distance 302 awayfrom a peripheral edge 314 of the substrate 104. In some embodiments,the horizontal distance 302 from the peripheral edge 312 of the firstring 148 to the peripheral edge 314 of the substrate 104 is about 2.5 mmto about 5 mm, for example about 3.2 mm. The inventors have observedthat maintaining a horizontal distance 302 of about 2.5 mm to about 3.5mm between the peripheral edge 312 of the first ring 148 to theperipheral edge 314 of the substrate 104 advantageously improves theability of the first ring 148 to shield the periphery of the substrate104 from deposition when the first ring 148 is moved to a position abovethe substrate 104, as discussed below.

Next, at 204, source material from the target 106 disposed opposite thesubstrate support 102 is sputtered to deposit a film atop the substrate104. In some embodiments, the source material may be a material such asa metal, metal oxide, metal alloy. In some embodiments, the sourcematerial may be copper. The inventors have observed that at thebeginning of the target life the deposition rate of source materialsputtered from the target 106 is greater proximate the center of thesubstrate 104 than the deposition rate proximate the peripheral edge 314of the substrate 104. However, over the life of the target 106 thedeposition rate at the peripheral edge 314 of the substrate 104 becomesgreater than the deposition rate at the center of the substrate 104.Though not wishing to be bound by theory, the inventors believe that thechange in deposition rate is due to the formation of an erosion groovewithin the target 106 over time. As the change in deposition rate occursover the course of the target life, source material will be sputterednon-uniformly onto the upper surface of the substrate 104 in a differentpattern over the course of the target life.

Next, at 206, the substrate 104 is lowered with respect to the firstring 148 from the first distance 300 to a next distance, for example asecond distance (e.g., by lowering the substrate support to a nextposition). The next distance decreases (i.e. is less than the firstdistance 300) over the course of a life of the target 106. For example,in some embodiments, a subsequent substrate is placed atop the substratesupport 102 and the source material from the target 106 is sputtered todeposit a film atop the subsequent substrate. The lowering of thesubstrate support to the next position and depositing a film atopsubsequent substrates may be repeated until the source material from thetarget 106 is consumed. The substrate support may be lowered betweenevery subsequent substrate processed or periodically for some subsequentsubstrates (e.g., after a predetermined number of substrates, aftermeasured film non-uniformity on a processed substrate exceeds apredetermined value, or the like). The amount by which the substratesupport 102 is lowered (i.e. the next distance) may be calculated usingthe formula described below. In some embodiments, the next distance mayeventually decrease to zero (where the substrate 104 and first ring 148are even with each other) or to a negative number (where the substrate104 is disposed below the first ring 148 rather than above the firstring).

The inventors have observed that, over the life of the target 106, thedeposition rate proximate the center decreases faster than thedeposition rate proximate the edge of the substrate 104 resulting in athicker amount of material proximate the edge of the substrate 104 thanproximate the center of the substrate 104. Shielding the periphery ofthe substrate 104 from deposition lowers the deposition rate at theperiphery, or edges, of the substrate 104 as compared to the center,which advantageously balances the overall deposition profile inapplications where the deposition rate proximate the center of thesubstrate 104 is lower than the deposition rate at the edge of thesubstrate 104. Thus, lowering the substrate support 102 from the firstdistance 300 to the second distance (or from any distance to a nextdistance) increases the amount of shielding of the periphery of thesubstrate 104 from deposition by the first ring 148. In someembodiments, as depicted in FIG. 3B, lowering the substrate support 102to the next distance eventually places the top surface of the substrate104 parallel to the top surface of the first ring 148. In someembodiments, as depicted in FIG. 3C, lowering the substrate support 102to a next distance 304 eventually places the top surface of thesubstrate 104 below the top surface of the first ring 148, for exampleabout 3 mm to about 10 mm below the first ring 148 (e.g., in someembodiments, a final distance). As depicted in FIG. 3B and FIG. 3C, asthe substrate moves to the next distance, the first ring 148 mayeventually be supported only on the top of the upwardly extending lip188 of the shield 174 by the ceramic isolator 141.

The distance by which the substrate support is lowered may be determinedempirically or by modeling. In some embodiments, the distance by whichthe substrate support is lowered may be determined using the formula1.1E⁵*X²−0.0167*X+0.2468, where X represents the target life (i.e., theamount of time the target has been running in kW/hr). The calculatedresult of the formula yields a number that represents the number ofmillimeters that the substrate support should be lowered with respect tothe initial position (e.g., the first distance). For example, with a newtarget, the substrate support may initially be positioned such that anupper surface of the substrate 104 is positioned at the first distance300 above the upper surface of the first ring 148. Upon completion ofprocessing of the first substrate or a number of substrates, the numberof kilowatt hours that the target has been running may be used in theabove formula to calculate a distance in millimeters that the substratesupport may be lowered to (e.g., to provide the upper surface of asubsequent substrate to be positioned at the next distance with respectto the upper surface of the first ring 148). Upon completion ofprocessing of a further subsequent substrate or a number of subsequentsubstrates, the number of kilowatt hours that the target has beenrunning may again be used to calculate the distance that the substratesupport should be positioned in with respect to the initial position ofthe substrate support. The continuous or periodic lowering of thesubstrate support may be continued until the target is completelyconsumed. When a new target is installed, the above-described processmay be repeated.

In some embodiments, the substrate support 102 is gradually lowered bythe calculated amount over the life of the target 106. Without wishingto be bound by theory, the inventors have observed that adjustment ofthe distance between the substrate 104 and the first ring 148 affectsthe plasma sheath. For example, when the first ring 148 is positionedbelow the substrate 104, for example at a first distance 300, the plasmasheath shifts down to the first ring 148 and out to the shield 174. Asthe substrate support 102 is lowered and the substrate 104 moves closerto and eventually below the first ring 148, the plasma sheath shifts upto the first ring 148 and then to the shield 174, which results inblocking deposition to the edge of substrate 104. The inventors haveobserved that moving the substrate 104 from the first distance 300 to anext distance less than the first distance 300 (and from any distance toa next distance) over the life of the target 106 can advantageouslymaintain non-uniformity at less than 2%.

Returning to FIG. 1, in some embodiments, a magnet 190 may be disposedabout the chamber 100 for selectively providing a magnetic field betweenthe substrate support 102 and the target 106. For example, the magnet190 may be disposed about the outside of the chamber wall 108 in aregion just above the substrate support 102 when in processing position.In some embodiments, the magnet 190 may be disposed additionally oralternatively in other locations, such as adjacent the adapter 142. Themagnet 190 may be an electromagnet and may be coupled to a power source(not shown) for controlling the magnitude of the magnetic fieldgenerated by the electromagnet.

A controller 110 may be provided and coupled to various components ofthe chamber 100 to control the operation thereof. The controller 110includes a central processing unit (CPU) 112, a memory 114, and supportcircuits 116. The controller 110 may control the chamber 100 directly,or via computers (or controllers) associated with particular processchamber and/or support system components. The controller 110 may be oneof any form of general-purpose computer processor that can be used in anindustrial setting for controlling various chambers and sub-processors.The memory, or computer readable medium, 114 of the controller 110 maybe one or more of readily available memory such as random access memory(RAM), read only memory (ROM), floppy disk, hard disk, optical storagemedia (e.g., compact disc or digital video disc), flash drive, or anyother form of digital storage, local or remote. The support circuits 116are coupled to the CPU 112 for supporting the processor in aconventional manner. These circuits include cache, power supplies, clockcircuits, input/output circuitry and subsystems, and the like. Inventivemethods as described herein may be stored in the memory 114 as softwareroutine that may be executed or invoked to control the operation of thechamber 100 in the manner described herein. The software routine mayalso be stored and/or executed by a second CPU (not shown) that isremotely located from the hardware being controlled by the CPU 112.

While the foregoing is directed to embodiments of the presentdisclosure, other and further embodiments of the disclosure may bedevised without departing from the basic scope thereof.

1. A physical vapor deposition chamber, comprising: a chamber bodyhaving a first volume; a chamber lid comprising a target assembly, thetarget assembly comprising a target, disposed atop the chamber body; asubstrate support disposed within the first volume, opposite the targetassembly, and having a substrate supporting surface; a shield disposedwithin the chamber body comprising one or more sidewalls configured tosurround the first volume, wherein the shield extends downward to belowa top surface of the substrate support, radially inward, and thenreturns upward to form an upwardly extending lip; a first ring having afirst portion and a second portion, wherein the first portion comprisesan opening having a ceramic isolator disposed therein, wherein theceramic isolator rests on the top of the upwardly extending lip of theshield, and wherein the second portion extends away from the firstportion toward the substrate supporting surface, and wherein thesubstrate support, over a course of a life of the target, is configuredto raise and lower, relative to the first ring, a substrate disposed onthe substrate supporting surface; and a second ring disposed about aperipheral edge of the substrate support and adjacent to the substratesupporting surface.
 2. The physical vapor deposition chamber of claim 1,wherein an edge of the second portion of the first ring is a distance ofabout 2.5 mm to about 3.5 mm from the substrate.
 3. The physical vapordeposition chamber of claim 1, wherein the substrate support comprisesan electrostatic chuck.
 4. The physical vapor deposition chamber ofclaim 1, wherein the target assembly comprises a source material and abacking plate to support the source material.
 5. The physical vapordeposition chamber of claim 4, wherein the source material is copper. 6.The physical vapor deposition chamber of claim 4, wherein the backingplate comprises a conductive material.
 7. The physical vapor depositionchamber of claim 1, wherein the first ring is electrically isolated. 8.The physical vapor deposition chamber of claim 1, wherein the substratesupport is configured to raise to an upper position, and, when thesubstrate support is in the upper position, the ceramic isolatorsupports the first ring on the top of the upwardly extending lip of theshield and the second portion of the first ring rests on the second ringat the outer periphery of the substrate support.
 9. The physical vapordeposition chamber of claim 8, wherein, when the substrate support is inthe upper position, the first ring surrounds the substrate support suchthat an upper surface of the substrate is positioned at a first distanceabove an upper surface of the first ring.
 10. The physical vapordeposition chamber of claim 9, wherein the first distance is about 3 mmabove the upper surface of the first ring.
 11. An apparatus forprocessing a substrate in a physical vapor deposition chamber,comprising: a substrate support disposed within a first volume of achamber body, opposite a target assembly that comprises a target and ispart of a chamber lid disposed atop the chamber body, and having asubstrate supporting surface; a shield disposed within the chamber bodycomprising one or more sidewalls configured to surround the firstvolume, wherein the shield extends downward to below a top surface ofthe substrate support, radially inward, and then returns upward to forman upwardly extending lip; and a first ring having a first portion and asecond portion, wherein the first portion comprises an opening having aceramic isolator disposed therein, wherein the ceramic isolator rests onthe top of the upwardly extending lip of the shield, and wherein thesecond portion extends away from the first portion toward the substratesupporting surface, and wherein the substrate support, over a course ofa life of the target, is configured to raise and lower, relative to thefirst ring, a substrate disposed on the substrate supporting surface.12. The apparatus of claim 11, wherein an edge of the second portion ofthe first ring is a distance of about 2.5 mm to about 3.5 mm from thesubstrate.
 13. The apparatus of claim 11, wherein the substrate supportcomprises an electrostatic chuck.
 14. The apparatus of claim 11, whereinthe target assembly comprises a source material and a backing plate tosupport the source material.
 15. The apparatus of claim 14, wherein thesource material is copper.
 16. The apparatus of claim 11, furthercomprising a second ring disposed about a peripheral edge of thesubstrate support and adjacent to the substrate supporting surface 17.The apparatus of claim 11, wherein the first ring is electricallyisolated.
 18. The apparatus of claim 16, wherein the substrate supportis configured to raise to an upper position, and, when the substratesupport is in the upper position, the ceramic isolator supports thefirst ring on the top of the upwardly extending lip of the shield andthe second portion of the first ring rests on the second ring at theouter periphery of the substrate support.
 19. The apparatus of claim 18,wherein, when the substrate support is in the upper position, the firstring surrounds the substrate support such that an upper surface of thesubstrate is positioned at a first distance above an upper surface ofthe first ring.
 20. The apparatus of claim 19, wherein the firstdistance is about 3 mm above the upper surface of the first ring.